fix: custom node example not fitting view

* fit view can't work (for the onLoad event) for elements assigned after the host has mounted (onMounted hook) as we can't calculate a rect of elements that don't exist at flow creation
* in this case just trigger fit view __after__ elements have been created/passed to the flow

Signed-off-by: Braks <78412429+bcakmakoglu@users.noreply.github.com>

src/composables/useZoomPanHelper.ts

@@ -23,9 +23,9 @@ export default (store = useStore()): UseZoomPanHelper => {
         bounds,
         store.dimensions.width,
         store.dimensions.height,
-        options.minZoom || store.minZoom,
-        options.maxZoom || store.maxZoom,
-        options.padding || DEFAULT_PADDING,
+        options.minZoom ?? store.minZoom,
+        options.maxZoom ?? store.maxZoom,
+        options.padding ?? DEFAULT_PADDING,
       )
       const transform = zoomIdentity.translate(x, y).scale(zoom)